Exporting video from app to phone gallery not working

I have been having trouble for a good while now exporting videos from the app to my phone.Both full length videos and clips from videos is stuck on 0% for a while and then says it's done.The file then appears in my gallery, but is broken and can not play.Same goes for taking a clip from a full length video and saving it in the app.This has rendered my gopro and app useless for a while and I hope someone has a fix.Video is 1080p 60fps recorded on gopro hero 5 black, phone is huawei p20 pro. Everything is updated to newest update.